Below is a list of Mass City MI zip codes. For your research we have also included Mass City Area Code, Time Zone, UTC and the local Ontonagon County FIPS Code. Each Mass City Michigan zip code has a center Longitude / Latitude point (the Mass City center is -89.080001831055 / 46.761600494385). For your convenience we have also indicated if that zip code in Mass City observes Daylight Savings time.